Tokyo Electric Power Company Holdings Inc. said Sunday it has completed removal of all 566 nuclear fuel assemblies from the storage pool of the No. 3 reactor building at the crippled Fukushima Daiichi nuclear plant, where a decades-long process to scrap the complex continues.

The No. 3 unit is one of the three reactors that suffered core meltdowns following the earthquake and tsunami disaster on March 11, 2011. There still are 1,007 fuel assemblies stored in the pools in the heavily damaged No. 1 and No. 2 reactor buildings.

Of the plant's six reactors, the company known as TEPCO finished retrieving stored fuel from the No. 4 reactor building in 2014. The Nos. 5 and 6 reactors were not operating when the quake struck and suffered little damage.

Removal of melted fuel debris at Nos. 1-3 units is another major challenge the company faces as it tries to clean up the complex in 30-40 years. The exact location of the debris in the reactors and ways to remove it have yet to be determined, with high radiation adding to the enormous difficulty of the decommissioning work.

The operator said it transported the last six fuel assemblies from the No. 3 reactor building to another pool on the complex premises at around 2 p.m. Sunday.

The reactor building of the No. 3 unit suffered severe damage following a hydrogen explosion on March 14, 2011, three days after the massive earthquake and tsunami struck.

At the time, 514 units of spent nuclear fuel and 52 unused ones were stored there.

TEPCO initially aimed to start removal of the fuel in late 2014 but repeatedly postponed the work due to high radiation levels in the No. 3 reactor building.

The operator installed a dome-shaped cover over the reactor building to prevent the spread of radioactive materials and started the fuel removal in April 2019.

Under the roadmap for decommissioning the complex compiled by TEPCO and the government, work to remove 615 fuel assemblies remaining in the No. 2 reactor's building will start between fiscal 2024 and 2026 and that for 392 fuel units from the building housing the No. 1 reactor between fiscal 2027 and 2028. The company's business year starts in April.

==Kyodo

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